Precision toolholder for boring machines and the like



W. BOREK April 24, 1945.

PRECISION TOOL HOLDER FOR BORING MACHINES AND THE LIKE Filed Aug. 11,1943 Patented Apr. 24, 1945 UNITED STATES PATENT OFFICE PRECISIONTOOLHOLDER FOR BORING MACHINES AND THE LIKE 4 Claims.

The present invention relates to machine tools and particularly to animproved tool holder for use in connection with a. boring bar, asutilized in horizontal or vertical boring machines, drilling machinesand the like.

One of the objects of the present invention is to provide a tool holderfor machines of the above indicated character, whereby the tool may beconveniently'and accurately adjusted and its adjustment can bepositively maintained for successive boring operations. A further objectof the invention is to provide a tool holding construction of suchcharacter that the cutting tool itself may be readily replaced when wornout, with the amount of metal in the discarded tool being held to aminimum.

The above and other advantageous features of the invention willhereinafter more fully appear from the following description, consideredin connection with the accompanying drawing, in which Fig. 1 is a viewin side elevation of a portion of a boring bar provided with a toolholder embodying the invention.

Fig. 2 is a transverse sectional view along the line 22 of Fig. 1,looking in the direction of the arrows.

Fig. 3 is a plan view of the parts shown in Fig. 1.

Fig. 4 is a perspective view on an enlarged scale of a tool socketremoved from the holder.

Fig. 5 is a perspective view of the adjusting member which cooperateswith the tool socket of Fig. 4.

Fig. 6 shows the tool holder of Fig. 1 following an adjustment of thetool therein.

For purposes of illustration, the invention is shown as applied to aboring bar I of conventional form, rotatable about its axis with respectto a cylindrical work-piece W and providing a transverse slot 2 forreceiving the shank 3 forming part of a tool holder which provides anenlarged head 4 projecting from one side of the bar I. The tool holderis clamped in position on the boring bar I by means of a set screw 5extending transversely through the boring bar to engage the holder shank3, as best shown in Fig. 2.

The tool holder head 4 provides a cylindrical opening 6 for receiving. acylindrical tool socket I and the socket l is adapted to be clampedwithin the head 4 by means of a screw 8 extending transversely across aslot 9 extending the length oi. the opening 6, so that turning of thescrew 8 will tend to contract the walls of the opening 6 upon the socketI.

As best shown in Fig. 4, the socket 'I provides an opening III forreceiving a cutting tool I l, with the tool 5 I being held in positionwithin the open-- ing ID by means of screws l2. The heads of the screwsI2 are countersunk within the socket I so 5 that .thelatter presents asmoothcylindrical outside surface adapted to fit closely within theopening 6 of the head 4. The tool socket I also provides an externalslot l3 which receives the end of a'screw l4 projecting into the opening5, as shown in Fig. 3, in order to always properly position the tool llcarried by the socket I when the latter is inserted in the opening 6 ofthe holder.

When the socket I carrying the tool H is assembled in the holder head 4,the lower end of the socket extends into a cross slot [5 provided by thehead 4 in communication with the opening 6. In this position the lowerend of the'socket l is in engagement with theupper face of an adjustingmember it which. as-best shown in Fig, 5,

is in the form of a circular disk having substantially the same diameteras the socket 1. The

adjusting member It further provides .a, threaded portion I! receivedina' similarly threaded opening I8 extending downwardly through the head4 into the shank 3. The existence of. the cross slot l5 exposes theperiphery of the adjusting member it, which provides a number; of toolreceiving openings l8 s that the: adjustingfmember may readily be turnedwithin the holder. p U

When theparts of the tool holder areinitialiy set up for theperformanceof. a cutting operation; the adjusting memberiBQ-isrtur'neddown into'theopening l8 smthat" it Dccu'piesthe positionof Fig. 1. The'tool sockfeti'l is then clamped in position by'thescrewgaifii ith theentlre tool holder-assembly then being; rotatablewithflthe boring bar by reason of; the clamping of the -holder shanklwithin the bar slot 2.

Assuming that a out has been taken with the initial setup of the tool IIas shown in Fig. 1 and it is desired to feed the tool outwardly for afurthercut, it is only necessary to turn the, adjusting member l6 bymeans of a suitable tool inserted in any one of the openings l9. Suchturning of the member I6 forces the tool socket l outwardly from withinthe holder, as indicated on a somewhat exaggerated scale in Fig. 6.0bviously, the amount that the cutting nose of the tool II is fedoutwardly can be controlled very accurately, even to one or twothousandths of an inch, dueto the fact that the slightest turning of theadjusting member It will cause a correspondingly slight movement of thetool socket 1. As an aid in definitely determining the amount '4 ofadjustment imparted to the tool H, the periphery' of the adjustingmember it provides a number of graduated scale markings 20 which may becalibrated with reference to an index mark 2| on the socket I. Sincethis index mark 2|, always occupies the same position with reference tothe head 4 by reason of the slot l3 and screw H, the markings 20 can beread directly so as to indicate, theactual-distance that the tool ll hasbeenfmoved outwardly for the-next cut.

Whenever it is desired to remove the tool ll for purposes of sharpeningor -renewing the same, 7 the tool socket 1 can be readily"withdrawnsfiom the holder head 4 upon loosening the screw is then asimple matter to-remove the tool':-rit--'-"' self from the socket 1 byloosening theutq ol hold ing screws I 2. Obviously, the amount of metalin the cutting tool H is reduced to a minimum by thepresentconstruction-sothat there is very' little waste of; metalwhen'Ka' tool isdiscarded I-claim: J v V I. A 'cutting' mechanism for"machine tools comprising in combination a rotary' tool parryextendingatright ,fa holderha'vinga and f3, enlargdfportroh" extendingbeyond the shafta "tool" socket 'reniovably mounted in "said enlarged*portion," saidfs'ocket providing means for clamping acutting-tooltherein, and an adjusting' member threaded relation .With said holderfor engaging 't'he innerfend, or said tool socket and -therebydetermining the 'extentf'to' yond the axis of-said shait.

"1 s magneti m iiil' f tools ro a y tq l'pa'rw;

which the cutting 'poiht or sa d-mo projects He;

aid shaft "opening and *an enlarged portion attending beyond .tiie' aidshaft opening r g xt nd n et i t *tool holdef'havinkja shaft, a toolsocket removably mounted in said enlarged portion, said socket providingmeans for clamping a cutting tool therein, and an ad- Justing memberhaving one portion in threaded 5 relation with said holder and anotherenlarged portion in abutting relation with the end of said tool socket,with said latter portion providing graduated; scale .markings'jtoindicate the extent 'of movementimparted to said tool socket by turn- 10; ing of said adjusting member.

A tool'holder for boring machines and the like, comprising a shank formounting in a roftatable boring bar, an enlarged head extending beyondthe;s hank providing an opening, a socket recqyamm said head opening andproviding means ior removably securing a tool therein,

0 means; forclamping said tool socket within the holder-for apredetermined setting of said tool, and an adjusting member in threadedrelation with the) shank of "said holder for ensuing said toolsocketilsaid adjusting member being turnable witl'i respect? to; socketfor feeding. the latter outwardly with respect' to ,the a iis of rotann. of theb me r- I f 1 4. A tbol' holder fforf ring emachines and the lk cq' irri ns s m 'gh fl it n in 8 m ablehbor'ing "fbar; 'anfenlarge'dhead extending beyond the shank providin'gldn opening, a socketreceivable.inisaidheadopening providingn'ieans'ior remolvably securing atool therein, means" for clampin ggsaid toolisocket within the holderfor a predetermined setting; of said. tool,

; and an adiusting,;meinber m1 threaded relation with said holderforengaging the innerrend 01' 35 said toolsocket, ,g said adjustinmember being accessiblel'thrg'ugh a fsl dt provided by said headandjlfi'roviding scalejm'arkin'gsito indicate the extentfofmovement'impartedto said tool, socket as aj resultbf, turning saidadjusting member.

Bonn:

